History is written by the winners, but the pens of historians cannot change DNA. The most comprehensive study of Britain’s Caucasian population to date shows that the Romans, Vikings and Normans all failed to leave their genetic markers on the native population of Britain.

While all of the invaders had a cultural influence, the DNA of Britains white population is most heavily influenced by the pre-Roman immigrants to the region. The only strong outside influence on the genetics of the population came from the Anglo-Saxons who account for 10 to 40 percent of the DNA of Caucasian Brits, depending on the region.

The analysis also found that there was no genetically distinct Celtic population outside of the Anglo-Saxon areas.

What the researchers found instead was a number of genetically distinct populations across the country. Those populations turned out to be distinct in some remarkable ways.

For example,the the counties of Cornwall and Devon, which neighbor one another, show more genetic differences than the populations of Scotland and England. The southern and northern parts of Pembrokeshire county in Wales also showed unexpectedly strong differences.

“Although people from Cornwall have a Celtic heritage, genetically they are much, much more similar to the people elsewhere in England than they are to the Welsh for example. People in South Wales are also quite different genetically to people in north Wales, who are both different in turn to the Scots. We did not find a single genetic group corresponding to the Celtic traditions in the western fringes of Britain,” Peter Donnelly of the Wellcome Trust Centre for Human Genetics in Oxford, UK told BBC News.

Only the Orkney Islands which were part of Norway for 600 years, were the only place where Vikings had a strong genetic influence, accounting for 25 percent of the local DNA.

The research was gathered by studying DNA samples from 2039 caucasian Britons. Each of the selected subjects for the study had four grandparents who were born within 50 miles of one another.

Those grandparents had an average year of birth of 1885, providing researchers with accurate local snapshots of the population of various region prior to 20th and 21st century immigration.

“Any one person’s genome is a random sample of DNA from all four of their grandparents, so it’s a way to look back in time,” Donnelly told New Scientist.

The researchers found 17 distinct clusters of genetic profiles which corresponded, almost exactly, to geographic location.

“We see striking similarities between the genetic patterns we see now and some of these regional identities and kingdoms we see in AD 60, and we think some of that may well be remnants of the groupings that existed then,” said Donnelly.

The largest of the clusters occupied almost all of the Midlands as well as southern and eastern England. This was the area most heavily influenced by the Anglo-Saxons however, even in those regions 60 percent of DNA came from pre-Roman immigrants.

Because so much of the DNA came from early settlers, the team was able to trace the paths of pre-historic immigrants.

The first immigrants to Britain came from northern Germany. Many of the 17 distinct genetic groups still share genomes similar to those of people in modern Belgium and Northern Germany. The other route of immigration was by boat from the west coast of France. Immigrants from that region also left genetic markers on caucasians in modern Britain.

This last is especially interesting in light of the discovery of ancient trade routes between pre-historic Britain and Europe.

Given the cultural impact of the subsequent invaders of Britain, the researchers believe that there must have been some prohibition against the ruling elites intermarrying with the locals.

“When you study the past through history, linguistics or archaeology, you learn about successful people. History is written by the winners, so much of current historical information is from a relatively small subset of people. Genetics, by contrast, is the history of the masses,” said Donnelly.

The full results of the research can be found in the journal Nature.